The function of human tissues and organs gradually deteriorates with age. Cellular damage or stress can also lead to cellular senescence, resulting in various tissue dysfunctions. In addition, oxidants produced by mitochondria accumulate with ageing and cause oxidative damage, which further accelerates cell and tissue ageing.

The lack of physical activity and deterioration of bodily functions caused by ageing can also lead to fatigue. Chronic fatigue can lead to physical dysfunction and lack of physical activity, triggering sleep disturbances. Studies have found that as we age, the production of melatonin and total cortisol hormone decreases at night, resulting in less rapid eye movement sleep (dreaming) and deep sleep, with deep sleep disappearing even after the age of 60. And since sleep is important for immune function and metabolism, age-related decreases in sleep quality may lead to the development of many age-related diseases.

Based on the different biosignals, we can divide the sleep process into three stages: wakefulness, rapid eye movement (REM) and non-rapid eye movement (NREM).

And as sleep is closely linked to immunity, cognition and metabolism, age-related declines in sleep quality may lead to the development of ageing-related diseases.

Current medications for insomnia can solve the problem but often have some side effects such as drowsiness and weight gain, so the search for new sleep therapies became crucial, and age-delaying NMN were a natural first research target.

In a recent article in the American Journal of Translational Medicine, a team of researchers who conducted a clinical trial on 58 middle-aged and older adults demonstrated that NMN significantly reduced the time to sleep, increased the duration of rapid eye movement and deep sleep, and improved sleep quality.


The researchers selected 58 volunteers aged 45-75 years and divided them equally into 2 groups, with the NMN group taking two 300mg NMN capsules (180mg NMN and 120mg starch) at noon each day and the control group taking two 300mg placebo capsules (consumed starch) at noon each day for 12 weeks. Sleep quality data were uploaded weekly as well as two Pittsburgh Sleep Quality Index (PSQI) surveys were administered.

I. NMN enhances sleep quality and increases the duration of deep sleep

Based on the experimental data, we found no significant difference in total PSQI scores and sleep latency between the NMN and control groups before treatment, while the difference was significant after treatment, especially in total PSQI scores. The total PSQI scores were lower in the NMN group compared to the control group, which means that the volunteers had better sleep quality after NMN treatment.

For the group, there were significant differences in total PSQI scores, sleep quality, sleep latency, sleep disturbance and daytime dysfunction before and after treatment in the control group, which could be due to the placebo effect; there were significant differences in total PSQI scores, sleep quality, sleep latency and daytime dysfunction before and after treatment in the NMN group.

According to the data from the sleep quality analysis of the experiment, changes in sleep duration and the proportion of REM sleep in the NMN group were observed from week 3 onwards, and by week 6 there was a significant change in the proportion of deep and light sleep, with a significant increase in the proportion of deep sleep and a significant decrease in the proportion of light sleep, suggesting that long-term NMN supplementation prolongs the duration of deep sleep.

In terms of total PQSI scores and sleep quality analysis, NMN improves sleep quality and increases the duration of deep sleep in middle-aged and older adults.

II. Results and Discussion

The specific mechanism by which NMN improves sleep may be related to the fact that NMN elevates NAD+ levels and activates the longevity protein sirtuins. Previous studies have found that sirtuins play a crucial role in the regulation of circadian rhythms. And sirtuins depend on NAD+ to function.

As we age, NAD+ levels also decline, negatively impacting circadian rhythms and leading to sleep disturbances. This may at least partially explain why older people taking NMN to increase NAD+ improve their sleep.

In the future we will be looking more closely at whether NMN follows circadian rhythms, whether the improvements in sleep last longer, and whether they continue to improve over time.

In addition, improved sleep quality in older adults may be just one of the many benefits of NMN to alleviate age-related diseases. Unravelling the wider benefits from NMN will require a large number of clinical trials, including neurological, cardiovascular and metabolic aspects.